Siren.



G. E. MARSHALL.

SIREN.

APPLICATION men lune z. 1915.

Patented Nov. 21, 1916.

Gordan EMa/Ja/l wiwi/1j We n0( YEQSES: l

Ann-onstaat UNITED STATES PATENT oEEIcE.

GORDON E. MARSHALL, 0F SANFRANCISCO, CALIFORNIA.

SIREN.

Application led J une 2, 1915.

To all whom t may concern Be it known that'I, GORDON E. MARSHALL, a citizen of the United States, residing in the city and county of San Francisco and State of California, have invented new and useful Improvements in Sirens, of which the following is a specification.

This invention relates to a siren suitable for use on automobiles, fog horns, or any place where it is desired to produce a far reaching sound.

One of the objects of the present invention is to provide a simple, substantial, easily operated siren which may be operated with a minimum expenditure of power, and in which the tone volume may be varied.

Further objects will hereinafter appear.

The invention consists of the parts and the construction and combination of parts as hereinafter more fully described and claimed, having reference to the accompanying drawings, in which- Figure 1 is a side elevation of the siren,

partly in section. Fig. 2 is a cross section on line 2-2, Fig. 1, looking in the direction of the arrow.

A indicates a cylindrical shaped casing, circumferentially of which is formed a plurality of equidistant ports 2. The rear end of the casing is inclosed, as indicated at 3, and provided with a central bearing 4, while the front of the casing is open and extended to form a horn 5. Journaled in bearings 4, and adapted to be rotated by means not here shown, is a shaft 6, and secured upon the shaft, by means of a key 7 is a disk-shaped rotor 8, on the forward face of which is hingedly secured, as at 9, a plurality of blades 10. These blades are adapted to be raised or lowered with relation to the face of the rotor by means hereinafter to be described.

Slidably mounted on the outer end of the shaft is a sleeve 11, and pivotally secured to the inner end of the sleeve is a plurality of links 12, one' for each blade 10; the inner ends of said links being pivotally secured to the upper end of each blade. A reciprocat Specification of LettersPatent.

Patented Nov. 21, 1916.

Serial No. 31,685.

shaped to straddle and engage the sleeve,

with a pawl and grip 15 engageable with a semicircular shaped rack bar 16 tolock the sleeve, with connected blades, in the open or closed position, or in any position intermediate thereof.

In operation, it is preferable to provide means for continuously revolving the shaft and rotor. In this instance very little power is required as the blades will normally lie in a plane parallel with the face of the rotor. Practically no resistance is created and the power consumed will be small. The moment it is desired to give a blast, it is only necessary to pull the lever in the direction of arrow a. Movement will then be transmitted to pull the sleeve, with connected blades, in an outward direction or the blades will be raised into a position approximately at right angles with the face of the rotor, a full blast or sound being immediately produced and projected by the horn.

In sirens now in common use the sound generally increases as the speed ofthe rotor increases and the sound volume is, therefore, small in the beginning and the tone is also often varied. In the present application this is entirely overcome and a full blast or tone volume is produced as the rotor is continuously revolving and the blades are quickly moved from one position to another. The tone volume may be varied, if desired, by changing the position of the blades. They may be moved to an angular position where the working area is less than when fully raised, as indicated at 17, in Fig. 1. The working area of the blades may be varied in proportion to the tone volume desired by changing the angular position, and the blades. may be locked in any position by the pawl and grip indicated at 15.

A siren constructed as here shown, when applied to` an automobile, may be continuously driven by a exible shaft in a similar manner to a speedometer and is, therefore, always ready to sound by moving the lever 13 inl one direction or the other to project or fold the blades upon the rotor. In other instancesV the rotor may be directly connected to an electric motor.v

The materials and finish of the several parts of the siren aresuch as the `experience and judgment of the manufacturer may dictate.

I wish it understood that various changes4 4 'in form, proportions and minor details of construction may be resorted to Within the scope of the appended claims, and that I do not Wish to limit myself to the speciic design and construction here shown. v

Having thus described mv invention, what I claim and desire to secure by Letters Patent is- 1. In a siren, the combination of a casing having aplurality of ports formed there" in, a rotor revoluble therein, and a plurality of blades pivotally mounted on the rotor.

2. In a siren, lthe combination of a 'casing having a plurality of ports formed therein, a rotor revoluble therein, a plurality of blades pivotally mounted on the rotor, and means Jr'or raising or lowering the blades with relation to the face of the rotor.

3. In a siren, the combination of a' casing having a pluralityr of ports formed therein, a rotor revoluble therein, a plurality of blades pivotally mounted on the rotor, a driving' shaft journaled in the casing upon which the rotor is secured, a sleeve slidably mounted on the shaft, links connecting the sleeve with the blades, one for each blade, and means for reciprocating the sleeve to -vary the position of the blades.

e. In a siren, the combination of a casing' havingI a plurality of ports formed therein, a rotor revoluble therein, a plurality of blades pivotally mounted on the rotor, a

driving shaft journaled in the casing upon which the rotor is secured, a sleeve vslidably ,ed in the casingy and engageable with the sleeve, and 'means' for loclring the lever.

5. In a siren, lthe combination of a casing havingg, a pluralityy of ports formed therein,

a rotor revoluble therein, ,a plurality of blades pivotally mounted on the rotor, a4

driving shaft journaled in'the casing upon which the rotor is'secured-,j'a sleeve slidably mounted on 'the,shat, links connecting the sleeve with thel blades,one for each blade,

means for reciprocating' ,the sleeve to vary.

the position of the blades, rvsaid means com- 1 prising a fork-shaped lever'pivotally mount-r ed in the casing and engageable with the sleeve, and means 'forlocking the lever against movement.v`

6. In a siren, the combination of a casing having a plurality of'portszformed therein, a rotor revoluble therein, a plurality of blades on the rotor, and means for increasing or decreasing th'e working area of the blades. f -v In testimonyv whereof I have hereunto set my hand inthe presence of two subscribing witnesses.

GORDON E. MARSHALL.

Witnesses:

R. W. DEWAR, F. STANwoon LocKE. 

